Hi, we will be staying in wengen on 8th & 9th dec 17. We plan to visit grindelwald after checking out on 10th dec early morning. We only have few hours to do it. As we need to catch the Golden pass line to montreux.

1. If we want to enjoy the MOB panoramic view , we would have to take the train at interlaken ost at 1:08pm. And arrive montreux at 4:13pm.

2. If we take the MOB belle epoque, time will be 3:08pm depart at interlaken ost. We can have more time in grindelwald but will miss the scenery on the way to Montreux cause it's getting dark.

I don't know whatthere is in Grindelwald to attract you to make it worth the detour. It is more commercial than Wengen, if that is your interest. Nice scenery, different perspective, same Alps, good base for trips to start hikes......

If you wish, assuming not too much luggage, you could take the cableways via Maennlichen,. Go from Wengen Wengiboden up to Maennlichen LWM, walk a few meters to Maennlichen GGM, ride own, then take the train out.

The timetable will give you those schedules. I believe they are the fastest route, so you would most likely not need to enter a "via."

If you are worried about your available time, I would go with Annika's option 1. Go down to Lauterbrunnen from Wengen and catch the first train out (platform 2), get off at Zweilütschinen, and then take the first train (platform 3) going up the other valley to Grindelwald. Once you are done there, catch a train (platform 1) that goes straight back to Interlaken. The train trip from Lauterbrunnen to Grindelwald takes about 40 minutes and the one from Grindelwald to Interlaken Ost will take a minute or so less. As for which train to take to Montreux, I would take the earlier one for the very reason you have mentioned.